My LO is 3 months and is drinking 5-6 oz at a time of formula. She eats SO SLOW! We are using Dr. Brown's Level 1 nipples and it takes her a good 45-1 hour to finish a bottle. Should we switch her? She does spit up sometimes right now, even an hour after feeding.
Re: When to switch nipples?
ETA: uhhh...I just realized the point of your post was that you want baby to eat faster. I'm dumb, ignore.
I agree that you should just try a faster one and see if that helps her eat faster w/o excessive spit up. OTOH, you don't ever have to switch. For DS1, he used level 1 nipples for a year, the whole time he used bottles. I figured that my nipples don't change over time when we are nursing, so why should his bottle nipples. He was never that slow from a bottle though. DS2 seems content with level 1, but he finishes a bottle in 15 minutes or so.